You omitted an important part of the sentence (in italics below):

> The MP initiated a conference call with Lockheed Martin engineers through the on-duty supervisor of flying (SOF). The MA held for approximately 50 minutes while the team developed a plan of action.

So it was the SOF on the conference call, relaying information to and from the pilot over the radio. This is more clear if you read the sequence of events on pages 7-10.

Not that it makes that much of a difference. Either way, he's up there waiting for the engineers on the ground to troubleshoot the problem.